Spark-plug tester.



W. M. NEAR.

SPARK PLUG TESTER.

APFLICATIQN FILED APR. 14. m1.

Patented Nov. 6, 1917.

' INSULHHON anucnl'oz WILIVIEK MNEHK UNITED STATES PATENT OFFICE;

' WiLMER. M. NEAR, or SHELBY; mrcn'rean.

SPARK-PLUG rns'rnn.

Specification of Letters Iatent.

Patented Nov, 6, 1917.

Application filed April 14, 1917. Serial No. 162,128.

article of this character which may be very easily carried in ones pocket or occupy very little space in'a tool box or kit, whereby it will be always at hand and capable of being quickly applied to the spark plug or plugs to be tested, and without the necessity of disconnecting the same.

A further object of the invention is improved spark plug tester embodying arelatively stationary electrode and a relatively movable or adjustable electrode with simple and efficient means whereby the last named electrode may be adjusted to increase or decrease the gap across the adjoining points or ends of the two electrodes, so as to determine the proper gap for the spark plug being tested at which the hottest and otherwise best spark will be produced -thereby.

And the invention also aims to generally improve devices of this class so as to render 3-5 them more useful and commercially desirable.

\Vith these and other objects in view, as will more fully appear as the description proceeds, the invention consists in certain r0 constructions. arrangements and combinations of the different parts that I shall hereinafter more fully describe and claim.

For a full understanding of the invention, reference is to be had to the following. de-

s'cription and accompanying drawing, in

which Figure 1 is a side elevation of a spark plug tester embodying the improvements of my invention, parts being shown in section.

Fig. 2 is a transverse longitudinal section/on the line 2-2 of Fig; 1.

Figs. 3 and 4. are detail perspective views of the contact members.

Fig. 5 is a detail view of a finger nut employed and hereinafter specifically referred to, and

Fig. 6 is a side view in applied position.

Corresponding and like parts are referred to in the following description and accomshowing the device panyingdrawing by like reference characters.

Referring to the drawing, the numeral 1 designates a block which may be formed of L any desired or suitable insulating substance or material, said block being substantially 'oblong in form, except that it is formedin one longer side witha preferably angular recess 2 which in the present instance em bodies two inwardly extending obliquely dis-'- posed surfaces 3 and 4. Secured to the surface 3 by means of screws or similar fastenlng devices is a metallic contact member and secured similarly to the surface 1 is a co'mplemental metallic contact member 6, these two members being designed respectively for engagement with the top screw at the top of the spark plug to be tested and the base of the plug.

The block 1 is formed with two longitudinally alined bores designated 7' and 8' re-'.'

spectively and intersected by a preferably circular opening 9 which extends'from one side face of the block to the other. The relatively stationary electrode 10 in the form of a metallic rod, as shown, is mounted in the bore 8 and preferably provided at its outer I end with a head 11,'the contact member 6 being provided with an angularly disposed extension 12 which extends over one, end of the block 1 and over and into contact-with said head. And the inner end of said electrode extends into the opening 9 where the gap is formed for the spark-to jump across.

13 designates the relatively movable or adjustable electrode of the device, and" this is received within 'the bore 7 hereinbefore mentioned, said electrode 13 being also com posed of a metallic rod formed intermediate" of its ends with screw threads 14 for engage ment by a preferably knurled nut 15 of fiber or the like provided with acentrally disposed washer 16 for direct engagement with the threads 14. This finger nut 15 is mounted within a transversely extending opening 1' formed in the block 1 and the electrode 13 is formed atits outer end with one=or more wings or vanes 17 as shown desi ned for engagement, in grooves formed in the wall or bore 17, whereby, as 18 manifest,

when the finger nut 15 is turned the electrode 13 will be moved toward or away from the ice electrode 10, so as to (decrease or increase the gap.

The contact member, is formed at one end with a lateral extension 19,-having an angu-' larly disposed extremity 18, the same .being designed to extend into an opening 20 fio'rmed in the blockin the inclined surface 3 thereof, said opening 20 communicating with the bore? and the extremity-18 bearing resiliently against the electrode 13 so as .to provide the required electrical connection.

From the foregoing description in con nectionwith the accompanying drawing, the operation-of my improved spark plug tester will be apparent In-the practical use of my-device, the contact member 6 is placed against the base of the spark plug to be tested,' and the contact member '5 against the top'of the plug, whereupon as is manifest, if the plug is working, the spark will jump across the gap'between the adjacent ends of the electrodes 10. and 13. By adjusting'the electrode 13 through the instrumentality of the finger nut 15, it is obvious that the approximate actual distance apart of the spark plug points may be determined, and by the experiments made with the device the points may be adjusted properly so as to securethe best results.

It will thus be seen that I have provided a very practical, durable and efficient construction of spark'plug tester, the parts-of which may be easily manufactured and readily assembled', and not liable to get out of order.

While the accompanying drawing illustrates what I believe to be the preferred em" bodiment of my invention, it is to be understood thatthe invention is not limited thereto, but thatvarious changes may be made in the construction, arrangements and'prc pon tions of the parts without departing rom the scope of. the invention as claimed.

What is claimed, is:

1: A spark plug tester, comprising abiock formed intermediate of its ends with a transversely extending opening, electrodes carried by said block in longitudinal alinement with each other and having their adjoining ends extending into said opening, and contact member's secured to one face ofsaid block, one or said contact members engaging with one of the electrodes and the other contact member being formed with a lateral extenmediate of its ends with a transversely extending opening, electrodes carried by'the block in longitudinal alinement with each other'and having their adjoining ends extending into said opening, contact members secured to one'face of"the-.block, one. of said contact members having a lateral extension projecting into .theblock into engagement with one ofthe electrodes and the other contact memberbeing formed with an angularly disposed extensionextending over the end of the block and over and. in.contact with the outer end of the other electrode 3. A spark plug tester'of the character described, comprising a block having two boresformed therein in longitudinal alinement with each other, and an opening separating said bores, a relatively stationary electrode mounted in one of said bores and extending into said opening, an electrode mounted in the other bore and formed intermediate of its ends with screw threads, a nut mounted in said block and 'eugageable, with the threads of said second named electrode, and contact members secured to the block and engaging the electrodes respectively.

4. A spark plug tester of the character described comprising a'block formed in one edge with twoinclined surfaces,v contact members secured to said surfaces, the block being formed with longitudinal bores in alinement with each other, and a transversely extending opening separatingsaid bores, a relatively stationary electrode mounted in one of said bores, one of said contact members being vformed with a life eral extension engaging the outer end of said electrode,'another electrode mounted in the other bore and formed intermediate of its ends with screw thre'adsand'a't one'eud with a wing engaging the wall of said bore, the block being formed with a transverse opening intersecting said bore, a finger nut mountedin said last named opening and engaging the threads of the second named electrode, the block being further formed in one of said inclined surfaces with an open:

ing communicating with the bore in which the threaded electrode is mounted and the other contact member being formedwith a lateral extension received in saidlast named opening and having an angular extremity engaging said threaded electrode.

In. testimony whereof I hereunto aflix my signature in the presence of two witnesses. WILMER M. NEAR. Witnesses W. E. Soo'rnn, Jnoon NEAR. 

